1. Field of the Invention
The present disclosure relates to a plasma ion source and a charged particle beam apparatus.
2. Description of the Related Art
Conventionally, a configuration for a plasma ion source is known, in which a flow restrictor is provided for restricting flow of gas introduced into a plasma chamber to generate voltage drop between a gas supplier and plasma in gas maintained at high pressure so as to suppress arc discharge (for example, JP-A-2011-142081).
In the plasma ion source of the related art, a cooling fluid channel is provided around a plasma generation chamber in order to cool a wall portion of a plasma generation chamber, the temperature of which easily increases due to contact with high-density plasma, and a coil which is easily heated by applying high-frequency power. Therefore, the entire size of the plasma ion source increases to several times that of the plasma generation chamber.